Fracture behavior of polymeric fiber reinforced lightweight structural concrete

Abstract

A study has been made of the effect of short randomly dispersed polypropylene fibers on the fracture behavior of lightweight structural concrete. Using unnotched and precracked beams subjected to bend loading, it was possible to determine the toughness factor TF and to estimate specific J integral parameters, namely J IC and J Max corresponding to the onset of fracture initiation and to the attainment of ultimate load, respectively. The results have indicated a considerable improvement in the fracture behavior associated with the presence of fibers. More specifically this improvement was manifested by a 400% increase in both TF and J IC .

Experimental Study on Size Effect and Fracture Properties of Polypropylene Fiber Reinforced Lightweight Aggregate Concrete

“…As a result, the increase in l ch on account of the increase of polypropylene fibers in LWAC exhibited lower brittleness and more ductile behavior. Such results following the addition of polypropylene fibers in LWAC have also been reported in previous research [11,45]. The relationship between the V pf (%) and the l ch (mm) is expressed as follows:…”

“…The G F reached almost the same values for different size notched beams at 1% volume fraction of polypropylene fibers. Incorporating polypropylene fibers increases the ductility and uniformly distributes the absorbed energy all around the bulk of LWAC specimens [45]. Thus, the polypropylene fibers could effectively decrease the dependency of G F on the size effect parameter, and the G F obtained from WFM for PFLWAC could be considered as a material property.…”

Mode I fracture toughness of fibre reinforced concrete

“…As has previously been mentioned, concrete is characterized by low fracture toughness [31]. The fracture failure at the microscope scale, irrespective of the external applied loading, is produced by local concentration of tensile stresses and strains near defects.…”